Question

А) 0.91 × (-10/13) - 4/7 ÷ 2 6/7

Answer 1

$a)0.91 \times ( - \frac{10}{13}) - \frac{4}{7} \div 2 \frac{6}{7} =$
$1) \frac{91}{100} \times ( - \frac{10}{13} ) = - \frac{7}{10} \:$
$2) \frac{4}{7} \times \frac{20}{7} = \frac{4}{7} \times \frac{7}{20} = \frac{1}{5}$
$3) - \frac{7}{10} - \frac{1}{5} = \\ \frac{ - 7 -2 }{10} = \\ - \frac{9}{10} = - 0.9$
$Ответ : - 0.9$

Answer 2

To solve the expression, let's follow the order of operations (PEMDAS/BODMAS):

1. Parentheses/Brackets
2. Exponents/Orders
3. Multiplication and Division (from left to right)
4. Addition and Subtraction (from left to right)

The expression you provided is:

0.91 × (-10/13) - 4/7 ÷ 2 6/7

Step 1: Start with the division operation.

0.91 × (-10/13) - (4/7 ÷ 2 6/7)

Step 2: Convert the mixed fraction into an improper fraction for easier calculations.

2 6/7 = (2 * 7 + 6)/7 = 20/7

Now, the expression becomes:

0.91 × (-10/13) - (4/7 ÷ 20/7)

Step 3: Perform the division.

0.91 × (-10/13) - (4/7 × 7/20)

Step 4: Simplify the expression further.

0.91 × (-10/13) - (4/20)

Step 5: Calculate the products.

-0.91 × 10/13 - 4/20

Step 6: Simplify the expression further.

-9.1/13 - 4/20

Step 7: To add or subtract fractions, they must have the same denominator. Convert -9.1/13 to a fraction with a denominator of 20.

-9.1/13 = - (9.1/13) × (20/20) = -182/260

Now the expression becomes:

-182/260 - 4/20

Step 8: Perform the subtraction.

-182/260 - 52/260

Step 9: Combine the fractions.

= (-182 - 52)/260

Step 10: Calculate the numerator.

= -234/260

Step 11: Simplify the fraction.

= -117/130

So, the final answer to the expression is -117/130.